Resistance device

ABSTRACT

A resistance device includes an impeller rotatably mounted on an impeller shaft and housed in an impeller housing, the impeller configured to act on an working fluid, a one-way drive assembly connected to the impeller shaft and configured to drive the impeller in one direction, the one-way drive assembly including a driving shaft connected thereto, a variable moment arm drive operatively connected to the driving shaft and configured to modify a distance between the driving shaft and a cable force vector applied to the variable moment arm drive, the variable moment arm drive including a cable connection portion, and a cable connected to the cable connection portion of the variable moment arm drive via a return spring, the cable configured to be pulled by a user.

CROSS-REFERENCE TO RELATED APPLICATIONS

Under 35 U.S.C. §119(e) this application claims the benefit of U.S. Provisional Application No. 61/972,650 filed Mar. 31, 2014, of which is hereby incorporated by reference in its entirety for all purposes.

BACKGROUND

1. Field

The present disclosure relates to devices for producing resistance against a user's motion, more specifically to devices for working out without the use of weights.

2. Description of Related Art

In exercise machines, when weights are lifted vertically (e.g., using cable and pulleys to translate vertical motion into some other vector), the force of gravity is constant, thus, the resisting force is also constant over the complete range of motion. However, this requires a plurality of weights which take up space and which have to be displaced from one location to another in order to provide a resistance. Such displacement can require a distance equal to the desired range of motion in order for the device to function, and/or a complex pulley or gearing system.

Rotary resistance devices (e.g., a rowing machine with a fan) cannot produce a constant force when the cable is pulled by a user at a constant rate since the resistance is a function of how quickly the blades of the fan turn and how much momentum the blades and/or working fluid have.

Such conventional methods and systems have generally been considered satisfactory for their intended purpose. However, there is still a need in the art for a resistance device that can produce a desired and/or constant force when a cable is pulled at a constant rate. There also remains a need in the art for such a device that is easy to make and use. The present disclosure provides a solution for this problem.

SUMMARY

In at least one aspect of this disclosure, a resistance device includes an impeller rotatably mounted on an impeller shaft and housed in an impeller housing, the impeller configured to act on an working fluid, a one-way drive assembly connected to the impeller shaft and configured to drive the impeller in one direction, the one-way drive assembly including a driving shaft connected thereto, a variable moment arm drive operatively connected to the driving shaft and configured to modify a distance between the driving shaft and a cable force vector applied to the variable moment arm drive, the variable moment arm drive including a cable connection portion, and a cable connected to the cable connection portion of the variable moment arm drive via a return spring, the cable configured to be pulled by a user.

In some embodiments, the one-way drive assembly can include a ratchet and pawl. The impeller can include a plurality of variable pitch blades. The resistance device can further include an impeller blade pitch control. The pitch control can have a setting for at least a maximum resistance and a minimum resistance.

The resistance device can further include a stator mounted inside the impeller housing adjacent to the impeller and configured to remove momentum from the working fluid.

The variable moment arm drive can include a cable wrapping surface having a cycloidial shape such that the moment arm changes as a function of a length of a cable pull to require a constant force input by a user. The variable moment arm drive can have a mechanical moment arm operatively connected to a controller, wherein the controller is configured to determine the distance between the driving shaft and the cable force vector and to set the mechanical moment arm to the determined distance to require a constant force input by a user.

In at least one aspect of this disclosure, a resistance device includes an impeller rotatably mounted on an impeller shaft and housed in an impeller housing, the impeller configured to act on an working fluid, wherein the impeller includes a plurality of variable pitch blades to modify a resistance, a one-way drive assembly connected to the impeller shaft and configured to drive the impeller in one direction, the one-way drive assembly including a driving shaft connected thereto, and a cable connected to the driving shaft, the cable configured to be pulled by a user. The one-way drive assembly can include a ratchet and pawl.

The resistance device can include a variable moment arm drive operatively connected to the driving shaft and configured to modify a distance between the driving shaft and a cable force vector applied to the variable moment arm drive, the variable moment arm drive including a cable connection portion. The resistance device can also include a pitch control including a setting for at least a maximum resistance and a minimum resistance. In some embodiments, the variable moment arm drive can include a cable wrapping surface having a cycloidial shape such that the moment arm changes as a function of a length of a cable pull to require a constant force input by a user. The variable moment arm drive can include a mechanical moment arm operatively connected to a controller, wherein the controller is configured to determine the distance between the driving shaft and the cable force vector and to set the mechanical moment arm to the determined distance to require a constant force input by a user.

In some embodiments, the resistance device can include a stator mounted inside the impeller housing adjacent to the impeller and configured to remove momentum from the working fluid.

The resistance device can include an automatic pitch control configured to determine a suitable pitch of the variable pitch blades to require a user to apply a constant force over a range of motion, the automatic pitch control configured to modify the pitch to the suitable pitch.

In at least one aspect of this disclosure, a exercise machine includes an impeller system connected to a drive shaft, a pull cable connected to the drive shaft, and a constant force system operatively connected to the cable and the impeller system such that the pull cable can be pulled at a constant force while maintaining a constant pull rate. The impeller system can include an impeller and a stator, the impeller configured to impart momentum on working fluid and the stator configured to absorb momentum from the working fluid.

In some embodiments, the constant force system can include a variable moment arm drive that varies the moment arm as a function of cable pull to account for impeller or working fluid momentum. The constant force system can include a plurality of variable pitch blades connected to the impeller to modify dynamically generated forces on the impeller to account for impeller or working fluid momentum.

These and other features of the systems and methods of the subject disclosure will become more readily apparent to those skilled in the art from the following detailed description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

So that those skilled in the art to which the subject disclosure appertains will readily understand how to make and use the devices and methods of the subject disclosure without undue experimentation, embodiments thereof will be described in detail herein below with reference to certain figures, wherein:

FIG. 1 is side view of an embodiment of a resistance device in accordance with this disclosure;

FIG. 2 is a partial, split perspective view of an embodiment of an impeller system in accordance with this disclosure; and

FIG. 3 is a partial, split perspective view of another embodiment of an impeller system in accordance with this disclosure.

DETAILED DESCRIPTION

Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. The systems and methods disclosed herein can be used for providing constant force resistance against a constant velocity cable pull for exercise and/or any other suitable use.

In at least one aspect of this disclosure, referring to FIGS. 1-3, a resistance device 100 can include an impeller system 101, a one-way drive assembly 105 connected to the impeller system 101, a variable moment arm drive 107 connected to the one-way drive mechanism, and a cable 109 connected to the variable moment arm drive 107.

The impeller system 100 can include an impeller 213 rotatably mounted on an impeller shaft (not shown in detail) and housed in an impeller housing 103, the impeller 213 configured to act on a working fluid using a plurality of fixed blades 215 of any suitable design. The working fluid can be any suitable fluid (e.g., air, water, oil) or any suitable viscosity. The working fluid can be a highly viscous fluid in some embodiments. In some embodiments, the working fluid can be sealed within the impeller housing 103.

The one-way drive assembly 105 is configured to drive the impeller 213 in one direction (e.g., counter clockwise or clockwise) and can include a driving shaft (not shown in detail) connected thereto that extends away from the impeller system 101. In some embodiments, the one-way drive assembly 105 can include a ratchet and pawl.

The variable moment arm drive 107 can be operatively connected to and/or disposed on the driving shaft. The variable moment arm drive 107 can include a cable connection portion where an end of the cable 109 connects to the variable moment arm drive 107. The cable connection portion of the variable moment arm drive can include a return spring attached to the cable 109 that is configured to retract the cable back to the variable moment arm drive 107 after being pulled out by a user. The cable 109 can include a handle 111 dispose on a proximal end thereof for a user to grasp and can be made of any suitable material (e.g., rope, wire, windings, chain).

The variable moment arm drive 107 is configured to modify a distance between the driving shaft and a cable force vector applied to the variable moment arm drive 107 when the cable 109 is pulled. In some embodiments, the variable moment arm drive 107 can include a cable wrapping surface with a variable shape (e.g., a cycloidial and/or frustoconical shape as shown) such that the moment arm changes as a function of a length of a cable pull to require a constant force input by a user. In this respect, as a user pulls on handle 111 (and the cable 109) away from the resistance device 100, the cable 109 will unravel on the variable moment arm drive 107 from a larger radius (right side) to a smaller radius (left side). Doing so will increase the force required to produce the same amount of torque on the impeller 213, however, the working fluid and/or the impeller 213 will have built up momentum requiring less force to be applied. In this manner, the decrease in force required to keep the impeller 213 operating at a given speed can be offset by the increase in required force due to the reduction in moment arm around the variable moment arm drive 107.

In some embodiments, the variable moment arm drive 107 can have a mechanical moment arm operatively connected to a controller, wherein the controller is configured to determine the distance between the driving shaft and the cable force vector and to set the mechanical moment arm to the determined distance to require a constant force input by a user.

In some embodiments, and as shown in FIG. 3, the impeller 213 can include one or more variable pitch blades 321 that are configured to change pitch relative to the direction of rotation such that the fluid dynamic forces applied to the working fluid can be modified. In such embodiments, the resistance device 100 can further include an impeller blade pitch control for manually or automatically controlling the pitch of the variable pitch blades 321. The pitch control can have a setting for at least a maximum resistance and a minimum resistance. In some embodiments, maximum drag (and thus maximum resistance felt by the user) may be achieved by setting the blades in a perpendicular manner to the direction of rotation. Certain blade configurations may require a different orientation for maximum resistance.

The resistance device 100 can further include a stator 217 mounted inside the impeller housing adjacent to the impeller 213 and configured to remove momentum from the working fluid to reduce the amount of momentum the working fluid can build up. The stator 217 may have stationary stator blades 219 of any suitable design and/or one or more blades may be variable pitch.

In at least one aspect of this disclosure, a resistance device can be similar as described above except having variable pitch blades 321 on the impeller 213 but no variable moment arm device 107 such that the variable pitch blades 321 change pitch during a pull of the cable 109 to keep the pull force constant at a constant rate of pull.

In at least one aspect of this disclosure, the resistance device 100 as disclosed herein can be used as an exercise machine. The exercise machine includes an impeller system 101 as disclosed herein connected to a drive shaft, a cable 109 as disclosed herein connected to the drive shaft, and a constant force system (e.g., a variable moment arm drive 107, variable pitch blades 321, or any other suitable system) that is operatively connected to the cable 109 and the impeller system 100 such that the cable 109 can be pulled at a constant force while maintaining a constant pull rate/speed. As disclosed herein, the impeller system 100 can include an impeller 213 and optionally a stator 217, wherein the impeller 213 is configured to impart momentum on a working fluid and the stator is configured to absorb momentum from the working fluid.

The apparatuses, systems, and methods of the present disclosure, as disclosed herein, provide for a constant force resistance device without the use of weights. While the apparatus, systems, and methods of the subject disclosure have been shown and described with reference to embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the spirit and scope of the subject disclosure. 

What is claimed is:
 1. A resistance device, comprising: an impeller rotatably mounted on an impeller shaft and housed in an impeller housing, the impeller configured to act on an working fluid; a one-way drive assembly connected to the impeller shaft and configured to drive the impeller in one direction, the one-way drive assembly including a driving shaft connected thereto; a variable moment arm drive operatively connected to the driving shaft and configured to modify a distance between the driving shaft and a cable force vector applied to the variable moment arm drive, the variable moment arm drive including a cable connection portion; and a cable connected to the cable connection portion of the variable moment arm drive via a return spring, the cable configured to be pulled by a user.
 2. The resistance device of claim 1, wherein the one-way drive assembly includes a ratchet and pawl.
 3. The resistance device of claim 1, wherein the impeller includes a plurality of variable pitch blades.
 4. The resistance device of claim 3, wherein the resistance device includes an impeller blade pitch control.
 5. The resistance device of claim 4, wherein the pitch control includes a setting for at least a maximum resistance and a minimum resistance.
 6. The resistance device of claim 1, further comprising a stator mounted inside the impeller housing adjacent to the impeller and configured to remove momentum from the working fluid.
 7. The resistance device of claim 1, wherein the variable moment arm drive includes a cable wrapping surface having a cycloidial shape such that the moment arm changes as a function of a length of a cable pull to require a constant force input by a user.
 8. The resistance device of claim 1, wherein the variable moment arm drive includes a mechanical moment arm operatively connected to a controller, wherein the controller is configured to determine the distance between the driving shaft and the cable force vector and to set the mechanical moment arm to the determined distance to require a constant force input by a user.
 9. A resistance device, comprising: an impeller rotatably mounted on an impeller shaft and housed in an impeller housing, the impeller configured to act on an working fluid, wherein the impeller includes a plurality of variable pitch blades to modify a resistance; a one-way drive assembly connected to the impeller shaft and configured to drive the impeller in one direction, the one-way drive assembly including a driving shaft connected thereto; and a cable connected to the driving shaft, the cable configured to be pulled by a user.
 10. The exercise machine of claim 9, wherein the one-way drive assembly includes a ratchet and pawl.
 11. The exercise machine of claim 9, further including a variable moment arm drive operatively connected to the driving shaft and configured to modify a distance between the driving shaft and a cable force vector applied to the variable moment arm drive, the variable moment arm drive including a cable connection portion.
 12. The resistance device of claim 9, further including a pitch control including a setting for at least a maximum resistance and a minimum resistance.
 13. The resistance device of claim 9, further comprising a stator mounted inside the impeller housing adjacent to the impeller and configured to remove momentum from the working fluid.
 14. The resistance device of claim 11, wherein the variable moment arm drive includes a cable wrapping surface having a cycloidial shape such that the moment arm changes as a function of a length of a cable pull to require a constant force input by a user.
 15. The resistance device of claim 11, wherein the variable moment arm drive includes a mechanical moment arm operatively connected to a controller, wherein the controller is configured to determine the distance between the driving shaft and the cable force vector and to set the mechanical moment arm to the determined distance to require a constant force input by a user.
 16. The resistance device of claim 9, further including an automatic pitch control configured to determine a suitable pitch of the variable pitch blades to require a user to apply a constant force over a range of motion, the automatic pitch control configured to modify the pitch to the suitable pitch.
 17. A exercise machine, comprising: an impeller system connected to a drive shaft; a pull cable connected to the drive shaft; and a constant force system operatively connected to the cable and the impeller system such that the pull cable can be pulled at a constant force while maintaining a constant pull rate.
 18. The exercise machine of claim 17, wherein the impeller system includes an impeller and a stator, the impeller configured to impart momentum on working fluid and the stator configured to absorb momentum from the working fluid.
 19. The exercise machine of claim 17, wherein the constant force system includes a variable moment arm drive that varies the moment arm as a function of cable pull to account for impeller or working fluid momentum.
 20. The exercise machine of claim 17, wherein the constant force system includes a plurality of variable pitch blades connected to the impeller to modify dynamically generated forces on the impeller to account for impeller or working fluid momentum. 